1. Field of the Invention
The present invention relates to a semiconductor device for sensing a physical quantity
2. Description of the Related Art
A conventional semiconductor device for sensing a physical quantity, for example, a pressure sensor or an acceleration sensor, often performs adjustment of characteristics by means of trimming in order to improve measurement accuracy. Patent Documents 1 and 2 (identified below), for example, disclose a trimming method for the characteristic adjustment of a semiconductor device for sensing a physical quantity in which electric trimming is conducted based on correction data, or trimming data, written in a nonvolatile memory such as an erasable programmable read only memory (EPROM) or an electrically erasable programmable read only memory (EEPROM).
Recently, semiconductor devices for sensing a physical quantity are required for higher performance; one product has a multiple of functions. Responding to the demand for higher performance, Patent Document 2 discloses a pressure sensor containing a temperature sensor. The technology in the Patent Document 2 carries out temperature detection based on a voltage value measured by a voltage measuring means when a predetermined current is supplied by a current generating means to the temperature detecting section.
[Patent Document 1]
Japanese Unexamined Patent Application Publication No. 2002-310735
[Patent Document 2]
Japanese Unexamined Patent Application Publication No. 2006-324652
In the case in which an additional function, or additional cell, such as a temperature sensor, is provided in an integrated circuit (IC) chip, however, a new output terminal generally needs to be provided for extracting an electric signal from the added cell and the output terminal needs to be connected to an electrode pad on the IC chip with a bonding wire. When a new output terminal is difficult to add, redesign is required, which leads to increased cost.